The Nature of Copper in Water and Wastewater

TABLE 5-8 Distribution of Soluble Copper in Natural and Treated Water and Wastewater 

Sample Copper added pg/liter pH HCOr mmole/liter Hardness, mg/llter as CaCOj Cu CuCO) Amino Inert Acid Humic Complex Complex Hexanol Extractable Cyanide complex, etc. 

Source M. I. Stiff. VVofer fleseorch, 5, 585-539 (1371), Reprinted by permission of Pergomon Press, Elmsford, N.Y, 

For the amino acids leucine, valine, alanine, serine, glutamic acid, aspartic acid, and tyrosine, the values of log range from 7 to 9 values of log jSa are in the approximate range of 14 to 16. The amino acid cysteine, which contains the -SH group forms an extremely strong complex with cuprous ion (Cu ) with a log /3t value of 19.5. 

As we will see later, humic acids are an extremely complex group of compounds. Because of this no one compound can act as a true model for this group. However, phenolic and carboxylic acid groups are common functional groups in humic acids. The substance 3,4 dihydroxybenzoic acid serves to illustrate one type of complexing group that may bind metals such as copper to humic acids  

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